Driving mechanism with pilot control



Oct. 2. 1951 F. B. SMALL 2,569,586

DRIVING MECHANISM WITH PILOT CONTROL Filed Sept 8, 1949 3 Sheets-Sheet l INVENTOR. ramme/v B. SMALL F. B. SMALL DRIVING MECHANISM WITH PILOT CONTROL Oct. 2, 1951 3 Sheets-Sheet 2 Filed Sept 8, 1949 'JNVEN TOR. km/216K B. SMALL WWW Oct. 2, 1951 F. B. SMALL DRIVING MECHANISM WITH PILOT CONTROL 3 Sheets-Sheet 5 Filed Sept '8, 1949 lllllll IHIIIIIIIIIIHH OuTPuISnarT 60\ {HI I Hflllllllllld? II III 7 ll llllllllll l ll'lll H IN V EN TOR.

7m (HUM/j m mm Patented Oct. 2, 1951 DRIVING MECHANISM WITH PILOT V CONTROL Frederick B. :Small, Waterloo, N. Y., assignor t Seneca Falls Machine Company, Seneca Falls, N. Y., a corporation of Massachusetts Application September 8, 1949, Serial No. 114,615

3 Claims.

This invention relates to a driving mechanism in which a relatively small pilot or control device renders a continuously rotated power member operative or inoperative with respect to a member to be driven.

As shown in the drawings, a power shaft is continuously rotated and a pilot or control device selectively couples an output shaft to said power shaft for rotation thereby.

In the preferred construction, the power shaft continously rotates in a single direction but the output shaft may be selectively rotated in either direction. 7

It is the general object of my invention to improve the construction of the coupling devices by which the power shaft is selectively connected to the output shaft.

A further object is to provide a construction in which the coupling devices are fully enclosed and effectively protected.

My invention further relates to arrangements and combinations of parts which will be'hereinafter described and more particularly pointed out in the appended claims. 1

A preferred form of the invention is shown in the drawings, in which v Fig. 1 is a plan view of my improved driving mechanism, partly in section;

Fig. 2 is a front elevation, looking in the direction of the arrow 2 in Fig. 1 and partially broken away to showinterior parts;

Fig. 3 is a diagrammatic view showing an application of the invention to a contour lathe;

Figs. 4 and 5 are detail sectional elevations,

taken substantially along the lines 4-4 and 5-5 in 'Fig. 1 and with certain parts omitted; and

Fig. 6 is a plan view of the associated driving drums and certain coacting parts.

Referring to the drawings, my improved driving mechanism is mounted in an outer casing C having partitions P and P (Fig. 1). The mechanism includes a power shaft [0 mounted in fixed hearings in the front plate of the casing C and in the partition P. The shaft I0 is continuously rotated from any convenient source of power, such as a motor M (Fig. 3), and a pinion I2 is fixed to its inner end.

Hollow. cylinders l5 and IE are mounted on ball or roller bearings l1 and I8, and the cylinder I5 is provided with a gear engaged by the driving pinion I2. The cylinder 16 is similarly mounted and is provided with a gear 2! of the same size as the gear 20and meshing therewith.

A perforated inner drum is mounted on a 2 1 shaft 26 preferably supported in a roller bearing 27 fixed in the partition P and itself supporting the ball bearings l1 previously described] A gear 30 is loosely mounted on the front end of the shaft 26 and may be adjustably secured thereto by a clamping screw 3 extending through a slot 32 in an arm 33 fixed on the shaft 26. The gear 30 is engaged by a gear 35 (Fig. 2) mounted on a pilot shaft which may be selectively rotated intermittently in either direction by suitable control mechanism. One such mechanism is shown in Fig. 3 and will be hereinafter described.

A driven drum (Fig. 1) is mounted adjacent the perforated drum 25'but slightly spaced axially therefrom. The drum 50 is mounted on a shaft 5| rotatably supported on a roller bearing 52 fixed in thev casing partition P, and a transmitting gear 54 is secured to the rear or outer end of the shaft 5|. The gear 54 continuously engages a gear 55 on the inner end of an output shaft 60, rotatably mounted in a fixed bearing 6|.

A spiral band (Fig. 6) encircles the associated drums 25 and 50, and the, narrow end 65a of the band is secured to the drum 25, while the wider outer end 65b is secured to the drum 50. On its outer surface, the band 65 is preferably provided with a friction surface 61 (Fig. 1), of sheet cork or some similar and equivalent ma: terial.

The construction'of the parts enclosed by the cylindrical casing 16 is identical with the parts associated with the casing I5 and above described, except that the spiral band 10 is oppositely Wound. The drum 25a in the casing I6 is mounted on a shaft 12 having a gear 13 adjustably secured thereto by an arm 14, and the gear 73 engages the pilot gear 35. The driven drum 500. (Fig. 6) is mounted on a shaft 15 supporting a gear 16 which engages. the previously identified gear 55 on the output shaft '60.

The spiral bands 65 and TB are so wound and tensioned that they normally contact the drums 25 and 5B or the drums 25a and Elia, and with their outer surfaces or cork facings just slightly clearing the inner faces of the continuously rotating cyclinders l5 and I6.

In the operation of my improved driving mechanism, the output shaft 50 is normally stationary and the pilot shaft 40 is also normally stationary but is subject to greater or less angular movement in a selected direction in accordance with the indications of a control or pilot device associated therewith,

If the shaft pilot 40 is slightly rotated anticlockwise as viewed in Fig. 2, the gear 30 and drum 25 will be correspondingly shifted clockwise, thus unwinding and expanding the band 65 (Fig. 6) and causing the band to be engaged by the cylinder I5 (Fig. 1) which is continuously rotated clockwise.

The band 65 and associated driven drum 50 will then be rotated clockwise by the rotating cylinder I5 until the drum 5!! has been turned an amount corresponding to the original displacement of the drum 25. Such rotation of the drum 50 will contract the band 65 and return it to its original position in which it clears the rotating cylinder Obviously, such shifting or adjustment of the driven drum 50 will cause corresponding but opposite movement of the output shaft 60 through the connecting gears 54 and 55, and will thus give the output shaft 60 an anti-clockwise adjustment corresponding in direction and extent to the original anti-clockwise displacement-of the pilot shaft 40.

During such adjustment, the drum 25a and 50a will be correspondingly but idly rotated in a direction to more tightly contract the band Ill, so that no driving relation will be established.

If the pilot shaft 40 is displaced reversely or clockwise, the band 10 will be expanded and will become operative, while the band 65 will remain contracted. The output shaft 60 will then be adjusted clockwise rather than anti-clockwise.

Provision is thus made for shiftin the output shaft 60 in either direction in exact correspondence with the selected movement of the pilot shaft 40 but without requiring the pilot shaft to provide power for such shifting of the output shaft. The power is provided by the power shaft I through one or the other of the rotatedcylinders I and I6.

Q In Fig. 3, I have shown an application of the invention as controlling the transverse position of a lathe tool T with respect to a rotated piece of work W, as in a contour lathe. The tool T is mounted on a cross slide 80 slidable crosswise on a carriage 8| which is moved longitudinally of the work on guideways 82 and 83.

A pattern plate N is mounted in fixed position and coacts with a detector or follower 85 pivoted at 86 on the cross slide 80 and having an insulated index arm 81 connected to a line wire L.

The free end of the arm 8'! makes selective contacts with terminals 90 and 9| which are connected to a relatively small control motor M through wires 92 and 93. The motor M is also connected to a second line wire L and is of the reversible type which will be rotated clockwise or anti-clockwise according as one or the other of the contacts or terminals 90 or 9| is engaged by the arm 81 under control of the pattern plate N.

The motor M is connected through reduction gearing G to the pilot shaft 4-0 which is rotatably mounted in the front of the casing C. The output shaft 60 is shown as provided with a pinion 95 engaging a rack 96 mounted on the carriage 80.

The operation of this illustrative mechanism may be briefly described as follows:

As the carriage 80 is moved longitudinally along its guideways, the detector or follower 85 follows the contour of the fixed pattern plate N. As the contour changes, the arm 81 swings to the right or to the left to engage one or the other of the contacts 90 or 9|. This causes the motor M to selectively rotate the pilot shaft 40 either clockwise or anti-clockwise. This movement of the pilot shaft 40 then causes the power shaft III to rotate the output shaft ,60 and rack pinion through the driving mechanism in the casing C as above described. The tool T is thus moved toward or away from the work W under the control of the pattern plate N, detector 85, motor M and pilot shaft 40.

It will be understood that the application of the invention as shown in Fig. 3 is illustrative only, and that the invention is well adapted for more general application.

The construction herein described has the substantial advantage that the drums and friction bands are enclosed by the cylinders l5 and I6 and are thus fully protected from dirt and in- Jury.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is:

1. A driving mechanism comprising a continuously rotated power shaft, an output shaft, a cylinder continuously rotated by said power shaft, a band enclosed by said cylinder but normally free therefrom, an operative connection from one end of said band to said output shaft, a pilot device, and an operative connection from said pilot device to the other end of said band, said pilot device being effective to expand said band to engage said cylinder by movement of said device, and said cylinder being effective to turn said output shaft until movement of said control device ceases and until said band is contracted by further .turning movement of said cylinder.

2. A driving mechanism comprising a continuously rotated power shaft,-an output shaft, a pair of cylinders continuously rotated by said power shaft but in opposite directions, a band enclosed by each cylinder but normally free therefrom, an operative connection from one end of each band to said output shaft, 2. pilot device, and an operative connection from said pilot device to the other end of each band, said pilot device being effective to expand either one of said bands in its cylinder by movement of said device in a selected direction, and the associated cylinder being effective through said selected band to turn said output shaft in a coordinated direction until movement of said control device ceases and until said band is contracted by further turning movement of said cylinder.

3. The combination in a driving mechanism as set forth in claim 2, in which said control device comprises a normally stationary control shaft, a reversible motor connected to turn said shaft by power in either direction, and selective means to energize said motor.

FREDERICK B. SMALL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Date 

